linux-kernel - Re: Expose 'array_length()' macro in <sys/cdefs.h> or <sys/param.h>

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <1aa963ec-0f44-4948-d862-7808b0b86a7a@gmail.com>
Date:   Wed, 30 Sep 2020 22:39:08 +0200
From:   Alejandro Colomar <colomar.6.4.3@...il.com>
To:     Joseph Myers <joseph@...esourcery.com>
Cc:     libc-alpha@...rceware.org, libc-coord@...ts.openwall.com,
        libstdc++ <libstdc++@....gnu.org>, gcc@....gnu.org,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        linux-man <linux-man@...r.kernel.org>,
        Jonathan Wakely <jwakely@...hat.com>,
        Florian Weimer <fweimer@...hat.com>,
        Ville Voutilainen <ville.voutilainen@...il.com>,
        enh@...gle.com, Rusty Russell <rusty@...tcorp.com.au>,
        Alejandro Colomar <colomar.6.4.3@...il.com>
Subject: Re: Expose 'array_length()' macro in <sys/cdefs.h> or <sys/param.h>



On 2020-09-30 17:58, Joseph Myers wrote:
> For some reason http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2529.pdf
> doesn't seem to have reached the agenda of a WG14 meeting yet, but adding
> a language feature like that to the standard would be another approach.
> 

Hi Joseph,

Yes, that would be great!

I hope they add that to the language. When/if that happens, nitems() 
could be `#define nitems(arr) _Lengthof(arr)` for std >= c2x.

In the meantime, I would add this macro to libc.

Maybe gcc could add such a great feature as an extension even before the 
standard does...

Too many wishes :)

BTW, I sent a PATCH v4 that I should've sent --in-reply-to PATCH v3 in 
this thread (but I forgot to do so); I'll link to it here:

https://sourceware.org/pipermail/libc-alpha/2020-September/117986.html

Thanks,

Alex